1. Field of the Invention
The present invention relates to a shielded electrical connector, particularly to a shielded electrical connector having two inner shielding shells enclosing two insulative partitions thus forming three ports for reception of three plug connectors.
2. The Prior Art
Multi-port connectors are popular for achieving compact size compared to simple stacks of several singleport connectors. U.S. Pat. No. 5,797,770 discloses a two-port shielded connector having two plug receiving cavities defined by an inner shielding shell fixed on a protruded portion of an insulative housing and an outer shielding shell encircling the insulative housing. The inner shielding shell is fixed to the insulative housing only by interference engagement to opposite inner walls of the housing. Moreover, the inner shielding shell is proximate to vertical sections of right angle contacts fixed to the housing. The inner shielding shell during assembling of the outer shell to the housing experiences a relatively great wiping force which may overcome the interference engagement between the inner shell and the inner opposite walls of the housing thereby moving the inner shielding shell to the vertical sections of the contacts. Additionally, the inner shell may be moved to contact the vertical sections of the contacts after several times of insertion/withdrawal of the plug connector. It is requisite to provide a new inner shell having a reliable retention to the housing and spaced away from the vertical sections of the contacts by at least a physical portion of the housing in order to guarantee that the inner shell will not shorten to the vertical sections of the contacts during insertion of the plug connector to the multi-port connector.
The two-port connector as disclosed in U.S. Pat. No. 5,797,770 has its vertical sections of contacts exposing to exterior without any metal shielding for prevention of EMI problem. Therefore, a rear shield is required to block the contacts in the rear side of the connector.
Moreover, the two-port shielded connector of the prior art can not be easily modified into a three-port connector because the registration of the vertical sections of the contacts will be a problem when the three-port connector is mounted on a printed circuit board. Therefore, in a three-port connector, an additional spacer device has to be used to solve the registration problem.
U.S. Pat No. 5,637,015 also discloses a two-port shielded connector having a locking plate integrally formed on a mating face of a front shell which encircles an insulative housing receiving a plurality of right angle contacts. The manufacture of the front shell is very difficult because the locking plate should be made by stamping and bending while its location across a central line of the mating face of the front shell will seriously hinder the bending of the cubic structure of the front shell and vice versa. For simplifying the manufacture, the locking plate should be made separately from the front shell for reducing manufacturing cost.